The characteristics of biological and non-biological materials are generally evaluated using physical or functional tests to determine or quantify one or more properties. For example, the strength or structural integrity of a material can be evaluated by subjecting it to physical challenges that test its response to stretching, twisting, compressing, heating, cooling, or other physical forces or conditions. For example, the physical properties of a synthetic scaffold material for tissue engineering can be evaluated by determining whether the scaffold is resistant to the type and amplitude of physical forces that it will be exposed to during cellularization and tissue growth in a bioreactor and subsequently after implantation into a recipient (e.g., a human recipient).
Materials can be inspected visually to determine whether they present any obvious visual signs of structural or functional failure. However, visual evaluation often is not sufficient to identify structural or functional deficiencies or to determine the extent to which a material has desired structural or functional properties.